================================================================== BUG: KASAN: use-after-free in debugfs_remove+0x10d/0x130 fs/debugfs/inode.c:690 Read of size 8 at addr ffff888089c19380 by task kworker/0:1/12 CPU: 0 PID: 12 Comm: kworker/0:1 Not tainted 5.1.0-rc4+ #66 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events __blk_release_queue Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x172/0x1f0 lib/dump_stack.c:113 print_address_description.cold+0x7c/0x20d mm/kasan/report.c:187 kasan_report.cold+0x1b/0x40 mm/kasan/report.c:317 __asan_report_load8_noabort+0x14/0x20 mm/kasan/generic_report.c:132 debugfs_remove+0x10d/0x130 fs/debugfs/inode.c:690 blk_trace_free+0x38/0x140 kernel/trace/blktrace.c:312 blk_trace_cleanup kernel/trace/blktrace.c:339 [inline] __blk_trace_remove+0x78/0xa0 kernel/trace/blktrace.c:352 blk_trace_shutdown+0x67/0x90 kernel/trace/blktrace.c:753 __blk_release_queue+0x1dc/0x3a0 block/blk-sysfs.c:866 process_one_work+0x98e/0x1790 kernel/workqueue.c:2269 worker_thread+0x98/0xe40 kernel/workqueue.c:2415 kthread+0x357/0x430 kernel/kthread.c:253 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 Allocated by task 24954: save_stack+0x45/0xd0 mm/kasan/common.c:75 set_track mm/kasan/common.c:87 [inline] __kasan_kmalloc mm/kasan/common.c:497 [inline] __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:470 kasan_slab_alloc+0xf/0x20 mm/kasan/common.c:505 slab_post_alloc_hook mm/slab.h:437 [inline] slab_alloc mm/slab.c:3394 [inline] kmem_cache_alloc+0x11a/0x6f0 mm/slab.c:3556 __d_alloc+0x2e/0x8c0 fs/dcache.c:1622 d_alloc+0x4d/0x2b0 fs/dcache.c:1701 d_alloc_parallel+0xf4/0x1bc0 fs/dcache.c:2449 __lookup_slow+0x1ab/0x500 fs/namei.c:1652 lookup_one_len+0x16d/0x1a0 fs/namei.c:2541 start_creating fs/debugfs/inode.c:313 [inline] start_creating+0xbf/0x1e0 fs/debugfs/inode.c:289 __debugfs_create_file+0x65/0x400 fs/debugfs/inode.c:352 debugfs_create_file+0x5a/0x70 fs/debugfs/inode.c:405 do_blk_trace_setup+0x376/0xb90 kernel/trace/blktrace.c:528 compat_blk_trace_setup+0x13e/0x1f0 kernel/trace/blktrace.c:623 blk_trace_ioctl+0x293/0x300 kernel/trace/blktrace.c:721 compat_blkdev_ioctl+0x461/0x1a60 block/compat_ioctl.c:402 __do_compat_sys_ioctl fs/compat_ioctl.c:1052 [inline] __se_compat_sys_ioctl fs/compat_ioctl.c:998 [inline] __ia32_compat_sys_ioctl+0x197/0x620 fs/compat_ioctl.c:998 do_syscall_32_irqs_on arch/x86/entry/common.c:326 [inline] do_fast_syscall_32+0x281/0xc98 arch/x86/entry/common.c:397 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139 Freed by task 16: save_stack+0x45/0xd0 mm/kasan/common.c:75 set_track mm/kasan/common.c:87 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/common.c:459 kasan_slab_free+0xe/0x10 mm/kasan/common.c:467 __cache_free mm/slab.c:3500 [inline] kmem_cache_free+0x86/0x260 mm/slab.c:3766 __d_free+0x20/0x30 fs/dcache.c:269 __rcu_reclaim kernel/rcu/rcu.h:227 [inline] rcu_do_batch kernel/rcu/tree.c:2475 [inline] invoke_rcu_callbacks kernel/rcu/tree.c:2788 [inline] rcu_core+0x916/0x13a0 kernel/rcu/tree.c:2769 __do_softirq+0x266/0x95a kernel/softirq.c:293 The buggy address belongs to the object at ffff888089c19340 which belongs to the cache dentry(33:syz1) of size 288 The buggy address is located 64 bytes inside of 288-byte region [ffff888089c19340, ffff888089c19460) The buggy address belongs to the page: page:ffffea0002270640 count:1 mapcount:0 mapping:ffff8880a3cf9e40 index:0x0 flags: 0x1fffc0000000200(slab) raw: 01fffc0000000200 ffffea00026de948 ffffea000213e308 ffff8880a3cf9e40 raw: 0000000000000000 ffff888089c19080 000000010000000b ffff8880a0018b80 page dumped because: kasan: bad access detected page->mem_cgroup:ffff8880a0018b80 Memory state around the buggy address: ffff888089c19280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888089c19300: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb >ffff888089c19380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888089c19400: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ffff888089c19480: fc fc fc fc fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================